


One Name, One Demon, One Brand

by Desdimonda



Category: Shall We Date?: Obey Me!
Genre: Biting, Blood, Desk Sex, F/M, Porn with Feelings, Possessive Behavior, Possessive Sex, Vaginal Fingering, Vaginal Sex
Language: English
Status: Completed
Published: 2020-08-27
Updated: 2020-08-27
Packaged: 2021-03-06 18:20:34
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,745
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26143249
Author URL: https://archiveofourown.org/users/Desdimonda/pseuds/Desdimonda
Summary: Mammon watches Neru help an Incubus, and doesn't like it. He doesn't like it at all. The closeness. The presence. The way others forget she's his, and no-one else's.And so he makes sure she remembers.----“Spare me the lecture. I’ve been here long enough,” she said cooly. “I’ve been around worse things than a horny Incubus.”Mammon smirked, stepping a little closer, closer, his horns extending with his steps, his fervour, the edges of his jacket brushing against the tip of her knees. “Oh yeah?”Neru chewed her pen. “Yeah.” She could see the movement of his jaw as he clenched it, teeth grinding as he tried to either contain his words, or find them. “There’s plenty worse in the Devildom,”she said. Neru clicked her pen on Mammon’s chest, lazily looking him up and down. His horns were fully crowned now, two black spirals printed by the orangey moonlight, their tips almost sharp enough to cut.
Relationships: Main Character/Mammon (Shall We Date?: Obey Me!), Mammon (Shall We Date?: Obey Me!)/Original Female Character(s)
Comments: 9
Kudos: 131





	One Name, One Demon, One Brand

**Author's Note:**

> This was part of a trade with [ otromeru ](https://twitter.com/otromeru) on twitter!!!   
> It was a pleasure and honour to write Neru. Thank you for trusting me, love.

Neru laughed again.

Mammon spun a ten grimm coin on the table loudly, hoping it would drown out her laughter, no matter how sweet it touched his ears. Because it wasn’t for him. 

The coin clattered on the old wood, and he spun it again, watching the gold catch the light of the common room as it sailed between his feet, propped ungainly on the table, scrunching a page of his textbook, forgotten.

“Would you move your gross feet,” said Belpegor as he snatched the book, batting away his foot. But Mammon just kicked back, settling his foot back onto the table harder as he knocked over a cup. “Idiot,” hissed Belphegor.

“Move if I’m in the way.” He said to Belphegor, but he looked to the side, watching. It was a mistake. He’d caught Neru just in time to see her move closer to the Incubus, an arm stretching across his chest as she pointed something out on one of his papers, strewn across their own private table.

The Incubus nodded quietly as Neru spoke, soaking up her voice that Mammon wished he could hear. He tried to imagine what she was saying, and for a moment he panicked, as if he couldn’t remember what her voice sounded like. He strained, pausing, listening, desperate for her to laugh again so he could remember.

_Of course you remember. She’s **all** you remember._

So why did she feel so far away, right now.

The coin fell, bouncing off the heel of his boot and he kicked it to the side, prying another glare from Belphegor.

“What’s your problem?” drawled Mammon, pulling over his cool, practiced facade. It was never enough to fool his brothers, though. It hadn’t lasted long on Neru either. But he still tried. Mammon picked up the coin and began to roll it between his fingers, waiting for Belphegor to bite.

“ _My_ problem? You’re like a child who missed his nap.”

“So, you.”

The end of Belphegor’s tail snapped against the table, tearing a sheet of paper. His horns weren’t out, he had either enough restraint or laziness to keep them at bay. But not his tail. Its thick fluff almost swiped the entirety of the tables contents to the floor.

Hiss. It trailed over books, papers, wood again. Once more, before Belphegor turned, and stared at Neru, who was chewing the end of her pen, words muffled by the plastic stuck between her teeth. 

Belphegor smiled, before he turned back to Mammon who was desperately trying to keep his attention on the coin still rolling between his fingers. “You know you could snap his neck with a finger,” said Belphegor almost wistfully. “Devour him in a second-”

“I ain’t gonna do that to Neru,” said Mammon, throwing the coin back on the table. “I ain’t you.”

A smirk tasted Belphegor’s lips as he continued to watch Neru and the Incubus, tilting his head to the side, as if imagining his suggestions.

Neru turned. She’d already felt their eyes on her before she heard the coin clatter on wood. It was Belphegor she saw watch her first. But she knew it wasn’t that gaze that’d stuck. Belphegor ignored her and turned back to his notebook, tail curling at his back lazily.

Mammon ignored her too, but plucked a feather from one of his boots, letting it fall to the floor. Another, the longer she stared. He’d already had to get them re-feathered since she’d arrived, after plucking them clean. 

“And this date - is it right?” asked Decara, the tip of his forked tail underlining the number of an important date in human history he’d scribbled in his notes.

“Hmm?” Absent, Neru touched the paper and nodded, looking back up at Mammon, his eyes catching her movements again. If he wanted to talk, come and talk. “Yeah. Good,” she said chewing her pen.

Decara’s tail tip wiggled side to side as he smiled, turning to the next page of his textbook, asking a question to Neru that went wholly unanswered. 

“He’s always like this when someone gets close to anything he likes,” said Decara, leaning back in his chair, stretching weary arms.”

“Huh?” Neru almost cracked her pen as she bit down. “Oh. Mammon.” 

“I’m surprised you have the patience for him, still.”

“Still?”

Decara looked to the side, casually locking his fingers. “You know, you humans don’t have much time like we do,” he began, his voice smooth, but careful. “And yet...Mammon has it. You’d think you’d be more...free, giving-” Decara shrugged. “Fun, with your time-”

Neru, smiled. Casually, she began to pack up her books, her folders, neatly tidying the papers together. “My time may be a blink to you,” she said, leaning a little closer, seeing the quiver of his tail. “But it’s mine.” 

She looked up in time to see Mammon stare, glasses off, the bright blue of his eyes pricked into their skin.

“If you ever want it to be-” started Decara, but Neru just stood, and underlined another date in his notes before dropping the pen on the table. 

“That date’s wrong. Later, Decara.” And with a playful flick of one of his horns, Neru turned, and left, giving herself a glance at Mammon, who traced every movement, heard every step, his eyes painting the way she left behind.

It had been easy to follow the trail she’d left behind. There was a shadow of predictability to her steps lately. Routine had fallen into their days, and Mammon had become a part of it. It wasn’t that he’d consciously taken to mapping her out, they’d just become so woven into each other since she’d arrived. She’d been his initial responsibility, afterall. Or that’s what he told himself.

So as he watched her slip into one of the old classrooms she liked to hang out - a sanctuary - Mammon followed. He knew RAD so well - but not. He walked the halls, passed the walls endlessly before Neru arrived. They had blended into nothing, but were almost everything. There were so many rooms here. Used and not. And Neru had picked this one in particular, tucked away by an old staircase that he couldn’t remember where it went to. Somewhere he didn’t care. But this was Neru’s corner, now. A nook of humanity carved within walls where there was very little.

No-one else seemed to care about it, here. Perhaps the demons and others were repelled by the mortality and humanity that lingered behind the door, perhaps they were afraid that she _wasn’t_ afraid.

They may have been repelled from here, but they were drawn to _her._ To her force in a way Mammon could recognise, but the weight of it would never quite reach his tongue, an admittance for no-one, least of all himself.

But that didn’t mean that he was going to let the way everyone else around her acted slide. Who were _they_ to lay claim and collect what they thought was in their grasp, when Neru was _his_ human, when he was her _first,_ the hierarchy already established with the brand placed on her skin, bolder, brighter, bigger, more beautiful than anyone else's. Had everyone forgotten how to read in the Devildom? Had they closed their eyes, when it suit?

Mammon clicked his tongue as he remembered the way that incubus had sat so close to Neru, Mammon desperate to rip the veiled excuses for her attention from his forked tongue. He should leave an offering of a similar face, a similar fate at his doorstep. A warning. A reminder who ruled these lands, because it seemed everyone had _forgot._

Mammon clenched his fist, long claws tipping into his palms. 

He wouldn’t do that to Neru. Anyone else, but Neru.

Pushing the door open with little care, Mammon strode inside, seeing Neru sitting on the end of one of the old wooden benches, notes and books at her side and back as she sorted them methodically into her folder, the soft tinny notes of music coming from her phone sitting on the adjacent desk. It was some mortal music in a tongue Mammon didn’t recognise.

She looked up, and paused. Curious, questioning. But also demanding. Minutes before in the dining hall hadn’t been lost on her, and it was probably the answer to her question, but she still asked.

However, Mammon was the first to speak. Seeing Neru sitting there, the scrap of moonlight - turned day - filtering through the old windows, broken by its cracks, patterns, dappling over her body painted her in an alluring beauty here that no-where else seemed to give. Maybe it was why she chose it here. Its canvas her found backdrop in a place that was so out of place for humans. 

“Having fun with that Incubus, huh?” he said, not even a hello.

Neru clicked off her pen. “He asked for my help with some human realm history,” she said, nothing but the truth. 

But the truth was always so clouded, muddied to Mammon, no matter where he looked, dampened with yellow. Tangents threaded off here, there, from what boiled beneath. Catastrophes brewing when what he wanted wasn’t in hands, somehow, someway. So many saw his greed as simply materialistic. But so many didn’t understand the gnawing underneath to have, to hold; the duality of his need to consume and hoard the entirety of what he wanted as just _his,_ no matter the manifestation, name - he looked up at Neru - or beauty. 

It scared him sometimes. But sometimes, it made him feel alive.

Mammon stopped before her, a feather falling off one of his boots. “I don’t like you hanging around him. You can’t trust an Incubus, y’know.” The tips of his horns were peeking through his white hair, now. The black spiral catching the strands. 

“Spare me the lecture. I’ve been here long enough,” she said cooly. “I’ve been around worse things than a horny Incubus.”

Mammon smirked, stepping a little closer, closer, his horns extending with his steps, his fervour, the edges of his jacket brushing against the tip of her knees. “Oh yeah?”

Neru chewed her pen. “Yeah.” She could see the movement of his jaw as he clenched it, teeth grinding as he tried to either contain his words, or find them. “There’s plenty worse in the Devildom,”she said. Neru clicked her pen on Mammon’s chest, lazily looking him up and down. His horns were fully crowned now, two black spirals printed by the orangey moonlight, their tips almost sharp enough to cut.

He stepped closer again, pushing Neru’s legs apart with his as he made room, his thighs pressing against the old wood as he towered over her, letting the silence hang. “I don’t want you getting close to him,” he echoed.

“You said that,” said Neru, looking up at Mammon, seeking his eyes through the yellow tint. They were narrowed, beneath tips of white that were growing long. She reached up and ran her fingers through the strands at the side, freeing them from beneath his glasses, feeling them slip against her skin. Gentle threads for a gentle heart, despite the front and the fangs. 

She saw the way his lip twitched, a whisper away from her palm. He was malleable beneath her touch, but he tried so hard to not be. Pushing against the impression that moulded his emotions, driving them to their peak. Neru wondered if his defiance was just a catalyst to help him feel more, sometimes. Whatever it was, she didn’t hate it. Because she pressed, she pushed.

“And I’ll say it again if I want,” said Mammon, grabbing her wrist and pulling it away from his face. He pushed in down onto the desk by her thigh, claws extending into the wood. “I gotta let everyone know who’s got the hierarchy here. Not them. But _me._ ”

Neru gasped a little at the touch on her hand, but didn’t flinch. She leant into it, and him, her thighs pressing against his, drawing him in. Inching him down. Neru lifted the pen from her other hand to her mouth and chewed, watching Mammon as he hovered above her, the nick of his fangs peeking between lips. “Hierarchy over what?” she said over her pen.

Mammon snarled, his fangs twisting over his lips, his horns seeming to move as the moonlight twisted around the spirals as he leaned forward and snatched the pen from Neru’s hand and dropped it to the floor. He took her hand, he took her lips, and gave an answer. 

“Not what,” he said against her lips as they kissed, the leather of Mammon’s jacket strong in the air as he moved, as his hand slid around her head to cradle with a fistful of hair as he leaned forward, dipping Neru back. "Who." He shuddered as he moved with Neru, his next word almost lost. "You." 

Neru could feel the taste of his fangs as they kissed, sharper today than yesterday, and she rolled her tongue over the tip of one, before letting her kiss touch the edge of his lips, his jaw, pick the soft skin at his ear. 

"Didn't ya hear me, huh?" 

Mammon plucked her chin with finger and thumb, pressing down hard on the hand he'd pinned on the table.

He was so consumed with his upper hand, he didn’t realise Neru’s. Her legs, pinched around his waist, locked, and pulled him closer as he held her place. Distraction was easy with Mammon. He was so consumed with what he wanted, you could almost take what you wanted, too.

Neru could feel the indents of his claws against his cheek. But not sore, just there. “It’s impossible not to when you talk so much,” she teased.

It worked, and he kissed her again. Devouring. He let her go, hands messily throwing off his jacket. The scent of leather, of dust, hitting the floor with a thud. He pulled her closer, her thighs dragging against the wood, the edges indenting the flesh. Hands scrambled beneath her skirt as they kissed, the tips of his claws scratching her skirt. Neru gasped through their kiss and he began to retract his claws, the sharp tips pulling back as he pushed his fingers up, and up, the indent of his fingers growing gentler, even if his touch had _not._

Mammon’s hesitation had snapped. Just like the wings that tore through his shirt, spreading with a yawn, metal tipped claws catching the light as they curved around.

He dragged two fingers along her underwear, already damp, and he pressed. Following with his touch, body, to body, breath snatched between a kiss that didn’t want to end. 

Neru gave him the satisfaction of a moan, printed to lips. A vibrato he felt, more than heard, the intensity of their kiss swallowing nearly all other sound, despite the silence that hung in the classroom. 

It was so loud for Mammon, and he pulled aside Neru’s underwear, sinking two fingers into her wet flesh, cradling her head with a palm. These claws were out. Catching. Threading through her hair. And he pulled. He moved with her head, a knee knocking on top of the desk as he knelt above, fingers never slipping out of place.

“Who’s talking now,” he said, as he curled his fingers between her slit, fingers and gold nails soaked. 

Neru smiled as she tugged on the bottom of his lip with her teeth, seeing the rise of his fangs. “Still you.”

Mammon snarled and rose onto the desk, pushing Neru with him, sliding across the wood at her rise. He kept his fingers between her legs, moving exactly how she liked. He saw the way her knees tried to push together, knocking against his thighs; the way she arched off the table that was now her bed; the way her eyes sprang open, shut closed, a rolling rock of pleasure falling into his palm that he wanted to own. 

His hand still cradled at her head, messing her hair. And he watched for a while, towered above, as he fingered. Greedily devouring the way her body moved. Giving, he gained so much. And he kept it, held it in his palm, amassing a wealth that surpassed anything else he’d ever touched. 

Did she know?

Letting free her hair, he dragged his hand down to her shirt, unbuttoning it in one swipe of his hand. Hand, hungry, slid across her bared skin, pushing aside straps and fabric, thumb caressing the push of her clavicle that moved beneath her skin as she breathed her bliss, as she sucked in a breath, and out with pleasure as his fingers moved.

He pinched her nipple, peaked and pink, and he heard his name whisper past her lips. Almost. It caught, half said. But loud enough to exist. He kissed her, trying to taste it. He wanted more. There wasn’t enough. 

He pinched her nipple again, rolling it between his fingers. And his name fell again. This time whole. Enough for Mammon to take. 

His fingers moved quicker, spurned on by her enthusiasm, by her quiet praise. There was only meant to be one name on her lips, one demon in her eyes, one brand on her skin. 

Knees biting the wood, he spread his legs to spread hers, and bent down, taking a nipple between lips, teeth, and pulled. But he was restless. Teeth and lips tore across her skin, leaving behind scorch marks as they wore a pathway to her neck, her ears, her cheeks, her lips. Restless. Restless. 

Neru arched suddenly as he circled faster with his fingers. And Mammon, to hold her in place, bit down on her shoulder. Fangs sinking in with a claim. He could feel her shudder, the sensation of his bite, fire. And he could taste her. A small weep of red touching his tongue. Humans always tasted sweeter than anything else. Neru, the sweetest of all.

“ _Mammon,”_ she breathed, so close to his ear, the word tipped in a moan. 

Mammon’s wings shuddered, spread out at his back as his name broke the quiet. He rolled his fingers more, faster, feeling her move, hearing her move. She was gentle with her noise, but not timid. Contained, but giving. With a messy, bloodied kiss against her shoulder, slipping; with a last curve of his fingers, wet and hot, he felt her come, the fire of her pleasure scorching against his ruby singed lips.

Everything was so fast, desperate. Mammon pulled back his hand, damp with _her_. He released her hair, twisted and a mess above the wood. He watched her try to regulate her breaths as she dipped her knees into his waist, as he undid his trousers. Quickly.

There was no reprieve as he leaned down closer, hands sinking into her hips as he pulled, hips colliding as his cock dragged against her underwear. Soaked. With a growl he pulled it aside, tearing it half apart with no apology, and holding her off the table with one clawed hand, the other holding her steady by the shoulder, palm to bloodied fang prick, he thrust.

Still sensitive from her climax, Neru whined, arching into his body, her shoulders the only part of her body touching the desk for a moment. He was not slow. He was not gentle.

He towered over Neru, his span of wings a reminder of both beauty and power as he looked down, the blue of his eyes bright behind those glasses, piercing. The blood on his lips, on his fangs, washed away by a hungry tongue.

“You remember whose you are huh? Who’s mark got there first?” he reached down and kissed it, feeling his power thrum beneath her skin, ignited by their linked desire, boiling beneath. 

Neru smiled, biting her lip. “Maybe.” She thought for a moment as he thrust, pulling her back into position each time, as she gasped, catching her moans in her throat, that she could use that seal any which way, to _her_ advantage. To show Mammon who _really_ could be in charge. But Neru sank into his possessiveness. She arched into his desire. She reached up, drawing a hand along the edge of his wing that she could reach, and caressed.

Mammon stumbled, his wings fluttering, snapping wide and wild from the touch. Their foreheads pressed together and he held her close. So close and tight, his knees boring into the wood as he almost lifted her off it. 

Hands slipped off her thighs and slammed down her own, pinning them by her head. Her hair was a mess, caught under their fingers, like cracks on the wood. Mammon was caught between wanting to stare at her beauty, to consume it, greedily until he could remember the strands of hair on her head. And wanting to devour her, eyes closed, picking her together sense by sense instead across her pedestal. 

Mammon huffed. _He_ sat atop a throne and looked down. But why did he always feel like he looked up at Neru, no matter his vantage, his power, his name.

Neru moaned shakily, turning into their clasped hands, a brush of hair covering fingers as he felt her climax again. This time, quicker, louder, sharper. Her eyes wide as his lips dragged down her chin, beneath, kissing the soft flesh as he counted the rhythm of her heartbeat, erratic.

She clenched tightly around his cock, she shifted her legs, pinching his waist, and Mammon staggered, forehead to her chest. And he thrust, and thrust, muffling his moans against her breasts as he felt her body shift against the wood with his desperation, over, and over, the clench of his his hands to hers, pinning her in place until- until-

He came, the snap of his wings wide, and wild, shuddering as he rode the waves of his orgasm, a snarl covering Neru’s skin, from chest, to chin.

Kisses smothered her skin, her neck and up, until they touched her ear, “No more Incubus’”

Neru turned into Mammon, her voice raw from the husk of her moans. “If it means I get this, just try stopping me,” she teased.

Mammon snarled, annoyed, as he tucked his face into her neck, the coil of his horns dragging along her chin.

But Neru could feel his smile against her skin, and she dragged her fingers through his white hair, nails scratching his scalp, lazily, as he sank down onto the table, at her side.


End file.
